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Chris Rowles Exercise 1 22/1/08 Part A. 1. What is a Project? A project is a file created for ArcView, regarding mapping. ) What does it contain? A project file contains Geographical data in the form of .AVL, .DBF, .DBG, .SBN, .SHP, and .SHX formats. Which translates to a vertex based geographical representation of the Earth. 2. Why did you have to update the project file for this exercise? The project file had to be updated because of the change in directory structure form when it was last saved, and as such, it needed to update in order to find it’s requisite components. 3. A shape file is a simple, non-topical file format for recording geographical location and it’s attributed information. The three required components for a shape file are: .SHP The feature geometry file . SHX The index for the feature geometry and .DBF The file in which attributed information is stored. Part B: 4. What is the distance between map units and distance units? Map units are used to translate non projected map data into a scaled visualizations, in other words, map units are used to determine scale. Distance units however, are displayed in the results of a measure tool, these measurements are not in scaled terms. Map units are the base increment in which the map is made, Distance units are the base unit in which the map is measured. 5.What is the scale of the view? Map units: meters Distance: Kilometres 6. What projection is applied to the view? The orthogrpahic projection is applied. Orthographic projection is a means of representing a three-dimensional objects in a two dimentional medium. It is a form of parallel projection, where in the viewing direction is not equal to the projection plane. This presenting the illusion of three dimentons. 7. What is the Scale of the Veiw? The scale of the veiw is 62,249,686:1 Meaning that the representaion of the world presentied, is 62,249,686 times smaller than actual. 8.What does the Scale mean? The Scale means that the representaion of the world presentied, is 62,249,686 times smaller than actual. 9. What are the names of the four selected cities highlighted in red? Toronto, Punte Arenas, Capetown, Roma 10. What is the distance of each town to the origin? Toronto: 6,300 km Punte Arenas: 6,280 km Capetown: 4,000 km Roma: 4,400 km Part C 11. What map units did you choose and why did you choose them? I chose decimal degress as my map units, as they presented me with accurate information when the distance tool was used. It also provides accurate geogrpahic data as decimal degrees is the increments used when WORLD MAP was created. 12. What distance units did you use? Mor eof a personal preference, on such a large scale, any other unit of measure woudl not provide any relivant data. And larger units of measure were available. 13. What distance is it from toronto to punte arandes? from quinto to manado? - toronto to punte anrandes: 11,000 km -Quinto to manado, passing the prime meridian, 16,755 km. Part D 14. paste the image in your report. Orthographic Hammer-Aitoff 15. For each projection, describe how shape, area, distance and direction are either preserved or distorted. Also discuss briefly the uses of each type of projection (use the HELP menu for this task). The projection in which the circles were drawn portrayed the lines of longitude to be paralel to each other, and with the distance between lines constant from pole to pole. This however, is not an accuate representation of the world, as the world is spherical, not cyllindrical as such a map would suggest. However, the Hammer-Aitoff projection projects the wolrd in a oliptical fashion. As in it, only the equator and prime meridians are straight lines, all other parallels curve towards the nearest pole, and are unequally spaced along the central meridian. As such, when the circles, which were drawn on a cyllindrical map, were morphed to confrom with the new projection. As the circles were based off of co-oridnates established by the lines of longitude and latitude. And when these lines warped to match the new projection of the earth, all co-ordiante data was also visibly squewed. The orthographic gall projection, however, still projects all lines of longitude as paralel, but the tropical and arctic lines are lightly scewed from the cylindricla map, where distance between the lines is represented more accuratly, this the cirlces in this projection, show more distortion the further they are form the equator, but this is only vertical distortion, not horizontal and verticle distortion as seen in the Hammer-Aitoff projection. Part E 16. When woudl you use the conical projection? The conical projection is best used for rthe veiwing of areas at the middle lattidudes because it portrays areas with very little distortion, and maintains scale. 17. What is the scale of the HAMILTON CMA shapefile? 1: 230,322 18. What is the scale of the MAJOR ROADS shapefile? 1:250,878 19. In what UTM zone is Hamilton located? 17 20 Hamilton